This thesis compares the success of natural and artificial forest regeneration on a windstorm area south of Črnivec pass. The windstorm area lies in the montane zone, where natural regeneration with restoration of forest functions are slower and hillside stability is lower. The study site comprised 10 pairs of experimental plots, where growth variables of planted seedling and natural dominant trees were compared. Vascular plant and tree cover degree as well as tree density were assessed on special vegetation plots. A negative correlation between density of 8 present tree species and Rubus sp. cover degree was confirmed. Planted Picea abies saplings reached 43.6 cm greater average height growth and 9.2 mm greater average root collar diameter (RCD) in comparison with P. abies dominant trees. Planted Acer pseudoplatanus saplings reached 90.9 cm greater average height growth and 6.9 mm greater average RCD in comparison with A. pseudoplatanus dominant trees. Both P. abies and A. pseudoplatanus planted saplings reached higher Free-to-Grow values as dominant trees of corresponding species. A. pseudoplatanus planted saplings have shown the greatest herbivore browsing damage. P. abies, A. pseudoplatanus, Fagus sylvatica and Abies alba dominant trees have shown greater vitality and less browsing damage than planted saplings. Natural regeneration success was indirectly supported with results from vegetation plot analysis, where tree density reached 16,500 trees per ha with mean cover degree of 2.9%. On vegetation plots pioneer tree species were better established than late successional tree species with mean cover degree of 3.8% and 2.1%, respectively. Artificial regeneration is a beneficial supplement to natural regeneration in case of strong erosion dynamics, slow natural regeneration and dense competing vegetation. For achieving adequate growth results with artificial regeneration, greater costs for browsing protection and weeding must be taken into account.
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